A frequency tunable liquid metal monopole antenna is introduced. The antenna is formed inside a microfluidic channel embedded within Polydimethylsiloxane (PDMS) substrate. The bottom side of the channel is sealed with 25μm thick liquid crystal polymer (LCP) layer in order to interface the antenna with a conventional microstrip feed line using the capacitive coupling mechanism. The physical length of the antenna is dynamically changed by using pumps to accomplish tunability over a wide frequency range. The concept is demonstrated through the design and experimentation of a 2.9:1 tunable monopole antenna that can operate between 1.7GHz and 4.9GHz.